There is no problem so far.
Durability It can not be judged because it does not require a comparable usable period,
Because it can be evaluated in terms of price, I think that I will order it when I need it in future.

It is used for drilling on the concrete surface which has passed a long time since construction. It was an easy task as it was not very hard. It can be said that the ability of the drill has been fully demonstrated.